what the heck am I doing wrong?? I tried that application that checks to see if the right ports ar open, it says that they are all blocked. I've turned off the firewall on my router, and windows firewall. Nothing seems to help. I'm so frustrated.

ok, downloaded FSHost, now what??

I've gone through the optimizing tutorial, I think I'm ready to go.

I fly online almost every day on SimAviators and I lead a tuesday night fsx flight.  U can catch me as G-RCH on the server simply visit the SimAviators website for information on daily flights.  Regarding multiplayer, If u try very hard...u can get gamespy to work by clicking alot on blank space when its trying to connect.  U can use FSHost alternatively as mentioned above, but we tried a new program yesterday that worked wonders....its callad Hamachi.  It allows u to direct connect in FlightSimulator to a Hamachi network that is running the game....I suppose it can be used for any game really.  We used it instead of FSHost for one night to test it, and its brilliant because u dont need to bother with the ports and anyone on the network can host a flight...you get no connection issues...its very stable...and its fast...IE the aircraft move very very smoothly in multiplayer....where FSHost is a bit jerky.  Also saw an improvement on FSCommander but in respect to range...but that could be my imagination....but its much smoother in refresh rates....so u can run higher frames....worth a try guys...u wont be sorry once u figure it out.